Genesis 2:18 And the LORD God said, “It is not good that man should be alone; I will make him a helper comparable to him."
The 1st mention of something not being good is when God spoke of man being alone. There is so many avenues on this but God designed man to have fellowship, relationship. What man needed most was a helper to be alongside him. She was taken from his side, not his head nor from his feet, being below him.